The present disclosure relates to a cleaning device having a mechanism of removing residual toner on an image carrier surface by means of a cleaning member.
In image forming apparatuses based on an electro-photographic system such as a copying machine, a printer and a facsimile machine, a developing agent in the form of powder is typically used, and an electrostatic latent image formed on an image carrier such as a photosensitive drum is visualized by using a developing device. Then the visualized image (toner image) is transferred onto a recording medium and subjected to a fixing treatment. The toner remaining on the image carrier surface is removed by a cleaning device, and a new toner image is formed.
The cleaning device has a cleaning member like a fur brush and a cleaning roller for removing toner from the image carrier surface, a recovery roller for recovering toner from the cleaning member, a conveyance spiral for discharging the toner scraped from the recovery roller surface, a toner receiving seal for partitioning the interior of a housing into a recovery roller side and a conveyance spiral side, and an end seal provided between the toner receiving seal and the housing.
Here, the toner receiving seal guides the toner scraped from the recovery roller surface by a scraper, to the conveyance spiral side to prevent it from going toward the recovery roller side (outer side of the housing). Therefore, the toner receiving seal is required to be in contact with the entire area in an axial direction of the recovery roller at a substantially constant contact pressure that will not scrape off the toner adhering to the recovery roller. On the other hand, the end seal is required to be in contact with the toner receiving seal at a considerable pressure for securely preventing leakage of toner from inside the housing.
However, at an elevated contact pressure of the end seal, the toner receiving seal receives pressure at both end portions from the end seal and the toner receiving seal deforms, so that the contact pressure of the toner receiving seal against the recovery roller also varies. As a result, there exists the problem that the toner adhering to the recovery roller is scraped off by the toner receiving seal, and leaks outside through the opening of the housing.
In this respect, a method for alleviating the pressing force exerted on the end portions of the toner receiving seal from the end seal is proposed. One known exemplary configuration includes a sheet-like guide member (toner receiving seal) that guides the toner removed by the cleaning portion to a cleaner case, and a sealing member for sealing both end faces of the cleaner case, wherein only a tip end portion of the sheet-like guide member is overlapped with the sealing member by providing the sheet-like guide member with a notch portion or by providing the sealing member with a notch portion or a step portion.